Chapter 2 - Chemistry Flashcards
What is ‘matter’?
Matter is anything that takes up space and has mass. It is helpful to remember that matter can exist in a number of forms including solid, gas, liquid or plasma.
What is 90% of the human body composed of?
Four different elements; carbon, nitrogen, oxygen and hydrogen.
What are the three best known subatomic particles?
These are positively charged protons, uncharged neutrons and negatively charged electrons.
What does each atom have?
Each atom has its own mass number, dependent on the number of subatomic particles in the atom. Protons and neutrons are assigned one atomic mass unit (AMU) each.
What is an Element?
A basic building block of matter, can not be broken down by chemical means.
What is an Atom?
The smallest unit of an element that still retains the chemical and physical properties of the element.
What is an Atom Number?
Represents the number of protons in the nucleus of an element. All atoms of an element have the same number of protons housed in the nucleus.
Which one of the following is the study of matter and the energy that causes matter to combine, break apart, and recombine in everything living and nonliving?
Chemistry
Which one of the following characteristics applies to both living organisms and nonliving things?
Composed of matter.
A mad scientist has ripped apart an atom and collected all the subatomic particles located in the nucleus of the atom. Which one of the following has he collected?
Protons & neutrons
Which one of the following statements is TRUE regarding the structure of the atom?
Most of the mass if an atom is due to its protons and neutrons
Which one of the following statements CORRECTLY describes the relationship between an atom and an element?
An atom is the smallest unit of an element that demonstrates all of the properties of that element
Isotopes of an element have the same ________, but different ________.
atomic number, atomic masses
________ bonds hold the hydrogens to the oxygen within a water molecule, and ________ bonds attract one water molecule to other water molecules.
Covalent, hydrogen
Carbohydrates have which one of the following characteristics?
They contain carbon, hydrogen, and oxygen in a ratio of 1-2-1.
DNA differs from RNA in that DNA?
contains deoxyribose
Most eukaryotic cells have a membrane-bound ________ that contains the genetic material.
Nucleus
Which one of the following structures is characteristic of BOTH eukaryotic and prokaryotic cells?
Plasma membrane
The total number of protons and neutrons in an atom can best be determined from which of the following?
Atomic mass
which one of the following is TRUE regards electrons, shells and energy?
Electrons are located in shells around the nucleus. As an electron moves to a shell further from the nucleus, it loses energy. In order for an electron to move closer to the nucleus, it must absorb energy.
Alpha helices and beta sheets are characteristic of protein in which structure?
Secondary structure
A student measuring the pH of the water in a fish tank found it to have a pH of 8. Which one of the following statements is TRUE regarding that solution?
The water is alkaline
The most important physical characteristic of lipids with regard to living organisms is that they __________.
are typically a form of waste product that is difficult to eliminate.
_______ is the study of matter and the energy that causes matter to combine, break apart and recombine in everything living and non-living.
Chemistry
________ is the capacity to do work-the capacity to cause some change in matter.
Energy
Two isotopes of the same element will have the same _____ but a different ____.
Atomic mass, atomic number
Isotopes are defined as the chemical species which have same number of protons but differ in the number of neutrons. It can also be said that they are the chemical species of the same element which have same atomic number but have different mass number.
which one of the following are an oligosaccharide?
Sucrose, lactose and maltose
A student has isolated a large compound (macromolecule) from cells. Chemical analysis of the compound shows that it is made up of the following elements: carbon, hydrogen, oxygen, nitrogen and sulfur. To which group of macromolecules does this compound most likely belong?
Protein
How is a water molecule put together?
Each molecule of water consists of two atoms of hydrogen and one atom of oxygen covalently bonded to each other
Which of the following characteristics applies to both living organisms and nonliving things?
composed of matter
Each of the following statements about carbon is TRUE EXCEPT which one?
Carbon can form strong hydrogen bonds with other elements
ions in body fluids of a human are referred to as _____
electrolytes
A solution has been prepared by mixing glucose in water. Which one of the following statements CORRECTLY describes this solution?
Water is the solvent, and glucose is the solute.
A research student is analyzing the nucleic acid of a virus ______
is a strand of DNA
Each of the following statements is TRUE regarding hydrogen bonds EXCEPT which one?
Hydrogen bonds are responsible for the attraction of Na+to Cl-.
Which of the following is a very important source of energy for nearly all cells?
glucose
Which of the following is a lipid?
cholesterol
Which of the following molecules is stored in adipose tissue and serves as an important source of energy for the human body?
triglycerides
Which of the following forms a bilayer structure that is found in cell membranes?
Phospholipids
- Phospholipids, arranged in a bilayer, make up the basic fabric of the plasma membrane. They are well-suited for this role because they are amphipathic, meaning that they have both hydrophilic and hydrophobic regions. Chemical structure of a phospholipid, showing the hydrophilic head and hydrophobic tails.
Molecules of life include which one of the following?
water, proteins, lipids, nucleic acids, carbohydrates
Which one of the following sequences is CORRECT in terms of level of organization from least to most complex?
Cells, tissues, organs, organ systems, organism
Which one of the following is TRUE regarding macromolecules?
Cells use certain macromolecules to store energy
Which one of the following is a molecule?
NaCl
Carbohydrates have which one of the following characteristics?
They contain carbon, hydrogen, and oxygen in a ratio of 1-2-1
Sucrose is an oligosaccharide made up of which of the following sugars?
Glucose & Fructose
- The most common disaccharide, sucrose, or cane sugar, consists of a glucose molecule bonded to a fructose molecule.
Body fluids in humans have a high buffering capacity because of _______
The presence of bicarbonate/carbonic acid buffer system
